The present invention generally relates to toilets and, more particularly, to vacuum toilet systems.
Vacuum toilet systems are generally known in the art for use in both vehicle and stationary applications. A vacuum toilet system typically comprises a bowl for receiving waste having an outlet connected to a vacuum sewer line. A discharge valve is disposed between the bowl outlet and vacuum sewer line to selectively establish fluid communication therebetween. The vacuum sewer line is connected to a collection tank that is placed under partial vacuum pressure by a vacuum source, such as a vacuum blower. When the discharge valve is opened, material in the bowl is transported to the sewer pipe as a result of the pressure difference between the interior of the bowl and the interior of the sewer line. Conventional vacuum toilet systems also include a source of rinse fluid and a rinse fluid valve for controlling introduction of rinse fluid into the bowl.
The components of a conventional vacuum toilet are typically provided separately and are overly difficult to assemble. The discharge valve is typically mounted in a first position, while the rinse valve is mounted in a second, separate position. A flush control unit (FCU) is mounted remote from both valves and provides control signals to the discharge and rinse valve actuators. Accordingly, various mounting brackets, tubing, and wires are needed to interconnect the various components, making assembly overly complicated and time-consuming.
In addition, the separate components used in conventional vacuum toilets make repair and maintenance overly time consuming and labor intensive. Maintenance concerns are particularly significant in aircraft applications, in which a number of subsystems are installed on board. According to general practice in the airline industry, each sub-system includes one or more components which must be replaced in the event of failure, such replacement components being commonly referred to as line replaceable units (LRUs). Presently, the entire toilet assembly is defined as the LRU for the vacuum toilet system. As a result, an airline must stock one or more replacement toilets in the event of a toilet failure, so that the replacement toilet may be swapped in for the faulty toilet. A xe2x80x9cbench testxe2x80x9d is then performed on the faulty toilet to determine which components have failed in the toilet. The faulty components are then repaired or replaced (which may include significant disassembly and reassembly of the toilet) so that the toilet may be reused on another aircraft.
Each of the steps performed during a toilet repair is overly difficult and time consuming. To remove an entire toilet assembly from an aircraft requires disassembly of at least four self-locking mounting fasteners, an electrical connection, a grounding strap, a potable water line connection, and a waste discharge pipe connection. Each connection may be difficult to access, and may require a particular tool in order to loosen and disconnect. The same connections must then be reconnected for the replacement toilet.
Even if it were possible to remove and replace a single toilet component, it would be overly difficult and time consuming to do so. Removal of a component would require disconnection of several wires and pipes, and the components are often located in areas which are difficult to access. Furthermore, it would be difficult to diagnose whether one component or several components had failed. There exists a multitude of combinations of simultaneous component failures, which may lead to trouble-shooting errors and the replacement or repair of non-faulty components.
Conventional vacuum toilets further fail to provide adequate feedback regarding valve position. Conventional discharge valves are typically driven by an electric motor actuator having mechanical limit switches and signal switches to control valve position. Such a switch is overly complicated to use and maintain. The switches must be precisely set to trigger at the appropriate time, and special tooling is often required to set the switch. In addition, by locating the switches in the actuator, they are subject to mechanical wear and contact erosion, which may alter the setting of the switch, thereby requiring re-setting. Furthermore, lubricant or other materials may migrate to the switches, causing switch failure. Most importantly, the conventional apparatus is unreliable since valve position is inferred from the actuator position. As a result, the conventional approach is not responsive to various failure situations where the actuator may be operable but the valve is not, such as when the linkage connecting the actuator to the valve is broken or defective.
In accordance with certain aspects of the present invention, an integrated valve set is provided for use in a vacuum toilet system including a waste receptacle defining an outlet, the waste receptacle having a rinse fluid dispenser associated therewith, a source of rinse fluid, and a sewer line placeable under partial vacuum. The integrated valve set comprises a discharge valve having an inlet in fluid communication with the waste receptacle outlet, an outlet in fluid communication with the sewer line, and a movable discharge valve member adapted to selectively establish fluid communication between the discharge valve inlet and discharge valve outlet. A rinse fluid valve has an inlet in fluid communication with the rinse fluid source, an outlet in fluid communication with the rinse fluid dispenser, and a rinse fluid valve member adapted to selectively establish fluid communication between the rinse fluid valve inlet and rinse fluid valve outlet, the rinse fluid valve member being coupled for rotation with the discharge valve member. The rinse fluid valve member is coupled for movement with the discharge valve member.
In accordance with additional aspects of the present invention, an integrated valve set is provided for use in a vacuum toilet system having a waste receptacle defining an outlet and a sewer line placeable under partial vacuum. The integrated valve set comprises a discharge valve having a housing with an inlet in fluid communication with the waste receptacle outlet and an outlet in fluid communication with the sewer line, and a movable discharge valve member disposed in the housing and adapted to selectively establish fluid communication between the discharge valve housing inlet and the discharge valve housing outlet. A flush control unit is operably connected to the discharge valve and has a housing attached to the discharge valve housing, the flush control unit including a position sensor for detecting the position of the discharge valve member.
In accordance with further aspects of the present invention, an integrated valve set is provided for use in a vacuum toilet system having a waste receptacle defining an outlet and having a rinse fluid dispenser associated therewith, a source of rinse fluid, and a sewer line placeable under partial vacuum pressure. The integrated valve set comprises a discharge valve having an inlet in fluid communication with the waste receptacle outlet, an outlet in fluid communication with the sewer line, and a movable discharge valve member adapted to selectively establish fluid communication between the discharge valve inlet and discharge valve outlet. An integrally mounted rinse fluid valve has an inlet in fluid communication with the rinse fluid source, an outlet in fluid communication with the rinse fluid dispenser, and a rinse fluid valve member adapted to selectively establish fluid communication between the rinse fluid valve inlet and the rinse fluid valve outlet.
In accordance with still further aspects of the present invention, a
Other features and advantages are inherent in the apparatus claimed and disclosed or will become apparent to those skilled in the art from the following detailed description and its accompanying drawings.